Expansion bend



W. PEUTHERT May 9, 1939.

EXPANSION BEND Filed Aug. 12, 1956 I buenf'or. I Wilhelm Peutheri Aiiarqey,

- ll stead of transversal folds, the benefit derived is thereby improving the f th u h t e tu e- 1.

i neutral zone of the elbow. Annular ribs [4 are provided for the same pur- Patented May 9 1939 i I UNITED STATES PATENT OFFICE 2,157,564 EXPANSION BEND Wilhelm Peuthert, Berlin-Blitz, Germany, assignor to Franz Seiflert & (10., Aktiengesellschaft, Berlin-Eberswalde, Germany Application August 12, 1936, Serial No. 95,512 In Germany August 16, 1935- 7 Claims. (Cl. 13850) This invention relates to curved flexible compressure in the tube, they may be interrupted at pensator tubes such as are inserted in pipe lines one or more places by sections or parts 80 of the for taking up expansion and relative displacetube pr p r which have an uninterrupted circuments of the individual sections of the line. lar cross section without folds.

By providing such tubes in the usual manner In the modification shown in Fig. 3 inwardly with transversal i. e. peripheral annular folds the directed folds 2 are used; in the modification flexibility of the tubes is increased in a very des Wn in 4 sp d folds 3 are used; and sirable manner. This expedient, however, is not in the modification shown in Fig. 5 double folds satisfactory since the flow through the tube is 5, B are used. This latter construction is parconsiderably obstructed and disturbed by the ticularly adapted for tubes of great diameter. 1. crosswalls of the folds. In the modification shown in Fig. 6 the tube 8 While known elbow tubes could be freed of has aga n fo ds l as in The 1111161 p obstructions by providing, in known manner, ll of these folds, however, is covered by lips 9 throughout their surface longitudinal folds inconnected or integral with the wall of the tube,

offset by the increased stiffness, since the long In t modification shown in Fi flatt nin tudinal fold stiffens the tube in a proportion inout of the folds i is prevented by ribs i3 bracing creasing with the distance of such fold from the the fo ds a t t e Wa l Of he ube- 20 The object of the invention is to avoid all pose ac in o 3: according to Fi 9 8 .5

these disadvantages. It is a curved compensator yoke or yokes l8, and according to Fig. 10 antube provided with longitudinal folds only in or chors traversing the folds., These anchors near the neutral zone where they have no detri- 20 can be arranged in a plane at right angles'to mental stifiening effect on the tube but, to the the axis of the tube or, to increase their yield- :5 contrary, considerably increase the flexibility-of ing capacity, they can be arranged obliquely or $5 the tube. can have a curved or undulated form. This will In the accompanying drawing some modiflcae be obvious to an expert.

tions of the object of the. invention are illus- In the modifications shown in Figs. 11 and 12 trated diagrammatically. th folds re welded to the tube proper. In both 80 1 s a sid view f a compens in cases, for greater strength of the tubes, the weldcordance with the invention, having the form of ing seams are remote from the roots or feet of lyrethe folds. According to Fig. 11 the welding 2 is a cross Section at the 11119 0f seams 26 are located at intermediate points of Fig. 1. the walls of the folds while according to Fig. 12

at Figs. 3 to 2 inclusive are cross sections o the welding seams 2e are located laterally m the modifications. walls of the tube proper. These welded construc- 13 1s a View of an elbow havmg a longl' tions make it conveniently possible to make the tudinal fold in combination with the known h rad m transversal-folds extending all around the pe- $132 2: z g gaiz 22. g er g e aterial.

riphery. 40

Fig. 14 is a view of a similar elbow with the 2 3 2 g g g transversal folds arranged at the inner curvana 0 as v as e tum (mm usual transversal annular folds all around its The lyre a shown in Fig. l-has a substantially penpherycylindrical cross section. Projecting outwardly The elbow shown 1h besides the 45 from th neutral zone ar t longitudinal fold longitudinal folds I, transversal folds 33 arranged which have a curved apex and flat walls sepaat e inner Curvature Onlyrated by an ample space. These folds increase I claim: remarkably the flexibility of the tube. They do 1. An expansion bend for pipe lines, said bend not, however, create any substantial resistance to consisting of a curved pipe having a continuous 50 flow. This is accomplished by extending the wall, formed by a single piece of sheet metal, folds in the direction of flow and so that they forming as well the inner as the outer part of do not project into the free cross section of the the bend, said parts being of smooth circular tube proper. cross section each except in the region of the To prevent flattening of the folds by the fluid neutral zone of the bend where the latter has longitudinal folds the opposite walls of which are separated by a free space.

2. A bend as in claim 1, said folds being arranged substantially outside said circular cross section.

3. A bend as in claim 1, said folds being narrow and having, in cross section, a curved apex with a very small radius and substantially straight nearly parallel sidewalls.

4. An expansion bend for pipe lines, said bend- 1 cross section each except in the region of the neutral zone of the bend where the latter has longitudinal folds, the opposite walls of which are separated by a free space, in which bendsaid folds extend uninterruptedly throughout the length of the bend, and in which means for counteracting flattening of said folds are provided.

5. A bend as in claim 1 in which means for counteracting flattening of said folds are provided in a zone substantially uninfiuenced by bending movements changing the curvature of the tube.

6. A bend as in claim 4, having a yoke member counteracting flattening of the folds.

7. A bend as in claim 4, having ribs bracing said folds. v

' WILHELM PEUTHERT. 

